The fixing of a flat tire for most automobiles involves several steps including:
1. Pulling safely to the side of the road.
2. Locating the tools.
3. Raising the vehicle.
4. Replacing the punctured wheel assembly with a spare wheel assembly.
5. Lowering the vehicle.
6. Stowing the punctured wheel assembly.
For the average motorist this task can be daunting at best. It needlessly exposes the motorist to inherent roadside dangers for long time periods. Over the past several years, the task of emergency tire repair has been addressed with a myriad of technologies. The traditional solution to an emergency flat tire repair has been the use of a compact or full size spare tires or the use of a towing service. Alternative solutions to addressing the problem associated with punctured tires include: (1) aerosol sealants to seal the hole/puncture and re-inflate the tire and (2) run-flat tires. All of these solutions are sub-optimal and many introduce more problems and higher costs.
Spare tires for their part are bulky, heavy, expensive, difficult to access and difficult to install. One solution which addresses many of the shortcomings of a spare tire, is aerosol sealant dispensers which combine a chemical fluid to be dispensed with a propellant. These are usually contained in a can or other type of container. A tube is attached between the can and a tire via a tire valve stem. The fluid is propelled through the valve stem into the tire. When the fluid flows through a tire puncture, it hardens with exposure to air. This forms a temporary repair of the tire. In theory, this method helps to eliminate some of the problems associated with tire repair. In fact, this method creates a more hazardous driving situation for the motorist. There is not enough propellant in the aerosol sealant container to properly and safely inflate the tire. Making this matter worse is the fact that the aerosol container becomes potentially explosive when stored in a vehicle operating in a climate where inside car temperatures can exceed 128 F. This can result in a very dangerous situation in which a partially inflated tire generates excessive heat due to repeated over-flexing which can cause the control of the vehicle to be compromised. A partially inflated tire will also cause premature tire failure.
A two-part system for repairing tires has been developed. The two parts include both a fluid sealant and a compressed air source. The compressed air source allows proper and safe inflation of the tire. It allows tire repair without raising the car. It allows safe handling and control of the vehicle due to properly inflated tires. Potential advantages of this two part system have not been realized for various reasons. Most solutions require air from the compressor to be forced into the sealant container through an intake. This results in sealant being forced out of the container and into the tire through an exhaust. This is very similar to the aerosol sealant described above except that compressed air is used to pressurize the sealant container. The many systems tend to be complicated and potentially unreliable. Most sealant delivery systems use a bottle to contain the sealant. The narrow opening of the bottle restricts the orientation of the sealant delivery system. The bottle must usually be oriented with the opening below the fluid. The bottle cannot be oriented on its side, i.e., horizontally. If oriented horizontally, roughly only half of the sealant will be dispensed.
Another disadvantage is hardening of the chemical sealant after use. While dispensing, sealant can contact outlet surfaces. These surfaces result in receiving a layer of hardened sealant. These parts of the dispensing device must be replaced. This is inconvenient for the user. Replaceable parts increase design complexity. This results in increased costs and lowered reliability. This is at best inconvenient. At worst, it can result in a user's vehicle being unrepaired.
One two part system uses a container of fluid tire sealant with an intake and an exhaust. A compressed air source forces compressed air through an intake into the sealant container. The resulting pressurized container exhausts sealant through an exhaust into the punctured tire. Potential advantages of this design are not realized because of the requirement for fluid container orientation. The container can be oriented so that the outlet is above the fluid. The device will simply pump air in this orientation. After use, the outlet of the device becomes contaminated with hardened sealant. If oriented horizontally, only roughly half of the sealant can be dispensed.
Another variation of this pressurized container method exists. In this method, the compressed air does not actually enter the sealant container. The compressed air fills and pressurizes a cavity around the sealant container. The sealant container has a movable piston at one end and the pressurized cavity causes this piston to push against the sealant in the container and the resulting pressure forces sealant through an exhaust into a punctured tire. A cap covering both the sealant container and pressurized cavity serves as a valve. This cap-valve allows the system to operate simply as a compressor passing air. This cap-valve alternately allows pressurized sealant to be injected into a punctured tire. This method seems to have an advantage of orientation independent operation, but this advantage is not realized. The combination of sealant container, cavity, and cap-valve increases complexity. This complexity increases the cost of the device. This complexity also reduces the system reliability. The portion of the cap-valve that comes into contact with sealant must be replaced. Sealant will harden when exposed to air or moisture. This portion of the cap-valve becomes useless due to hardened sealant.
Another device has a container of sealant fluid that is inside of a pressurized chamber. During use, the chamber is pressurized. This crushes the sealant container forcing sealant through an outlet. The advantage of orientation independent operation is not realized in this design because hardened sealant on the outlet parts requires replacement of these parts and the crushing of the container requires a flexible container. The container must be replaced after use and sometimes does not crush completely so that all of the sealant fluid is not delivered to the outlet and fluid that remains in the container is wasted. During replacement, this fluid can contact the user's skin. Depending on the chemical composition of the fluid, this may be hazardous.
An integrated compressor and sealant dispensing device also exist. This device includes a valve that switches the compressed air between air and sealant, and air only. This device uses a bottle of sealant with a metal or polymer seal instead of a cap. This device has the apparent advantage of ease of use. It's advantages are not realized because the valve that switches between sealant and air must be replaced after injecting sealant. This is very inconvenient, complicated, and adds cost. The sealant container uses a small mouth bottle which restricts its allowed orientation. The container's metal or polymer seal requires puncturing before use and the device uses a fairly complicated piston puncturing device. In addition, loose fragments of the punctured seal can be passed into the tire's valve core and this can result in the tire valve not functioning correctly so that air may leak from the tire while driving which negates any repair that may have been attempted.
A typical sealant injection unit exists. This unit provides a standing surface on its side which seems to allow a preferred sealant container orientation. However, this is not realized because the sealant container uses a narrow mouth so that the container must be oriented above the injection unit. The standing surface is on the bottom “side” of the injection unit. The container in this unit uses a metal or polymer seal and the seal must be punctured before injecting into a tire so that fragments of the punctured seal can impair the tire valve function which causes air to leak from the tire while driving after the sealant is injected which negates any repair that may have been attempted. In addition, the sealant container must be connected just before injecting sealant in order to puncture the seal which is inconvenient for the user.
Another sealant injection system exists. This system integrates a sealant container with a compressed air source which has the apparent advantage of allowing the user one button flat repair. This advantage is not realized for several reasons. First, this device requires the user to connect the sealant container just before use (which is inconvenient for the user) and the sealant container must be pneumatically connected to the compressed air source. Second, this device requires the user to screw the container into a special receptacle and the sealant container is a small mouthed bottle. After attaching, the container is oriented so the opening is at the bottom and screwing the bottle onto the special receptacle punctures the seal so that loose fragments of the punctured seal can impair the tire valve function which may cause air to leak from the tire while driving after the sealant is injected which negates any repair that may have been attempted.
A device for dispensing sealant is also known wherein the outlet is at the base of the sealant container and the device must be oriented vertically for the sealant to dispense. The base is the smallest face of the container so that orienting the device on the base causes it to be unstable and can fall over while sealant is dispensing. In addition, if the user does not re-orient it, all the sealant will not dispense so that sealant is wasted.
Another sealant dispensing device is described that is a cylinder with check valves at each end. The outlet of the device is shown in the center of the circular end of the cylinder so that the device must not be tipped so that the outlet is above the inlet. If the outlet is higher than the inlet, only air will pass through and the sealant will not be forced out. Therefore, this device must be oriented with the outlet below the inlet and must be tipped at an angle. In addition, sealant must remain below the air while dispensing.
Thus, it is desirable to provide an integrated compressor device and sealant container that overcomes the limitations of the above typical systems and devices and it is to this end that the present invention is directed.